Examine source code of FB-TW-IG ID

{
  "manifest_version": 2,
  "name": "FB-TW-IG ID",
  "version": "1.0.13resigned1",
  "description": "Facebook-Twitter-Instagram ID",
  "icons": {
    "128": "icon.png"
  },
  "page_action": {
    "default_icon": "icon.png",
    "default_popup": "popup.html",
    "browser_style": true,
    "show_matches": [
      "https://*.facebookcorewwwi.onion/*",
      "https://*.facebook.com/*",
      "https://*.twitter.com/*",
      "https://*.instagram.com/*"
    ]
  },
  "permissions": [
    "https://*.facebookcorewwwi.onion/*",
    "https://*.facebook.com/*",
    "https://*.twitter.com/*",
    "https://*.instagram.com/*",
    "activeTab",
    "clipboardWrite"
  ],
  "applications": {
    "gecko": {
      "id": "{0cc9cf8c-a264-47ed-a6a5-033ea7b82128}"
    }
  }
}